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<?php $array = ''; $array['a']['b'] = 1; var_dump($array);
Output for 8.0.0 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.19, 8.3.0 - 8.3.7
Fatal error: Uncaught TypeError: Cannot access offset of type string on string in /in/1psrC:4 Stack trace: #0 {main} thrown in /in/1psrC on line 4
Process exited with code 255.
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33
Warning: Illegal string offset 'a' in /in/1psrC on line 4 Fatal error: Uncaught Error: Cannot use string offset as an array in /in/1psrC:4 Stack trace: #0 {main} thrown in /in/1psrC on line 4
Process exited with code 255.
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33
array(1) { ["a"]=> array(1) { ["b"]=> int(1) } }

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